1. Field of the Invention
The present invention relates to a device for mounting and connecting at least one power semi-conductor component to a unilateral heat sink. Such a device comprises the heat sink and a clamping device associated with each semi-conductor component for applying it against the heat sink and bearing, on the heat sink and on the semi-conductor component through a connecting bar.
Known mounting devices for power semi-conductors with unilateral cooling. that is to say provided on a single face of the semi-conductor, sometimes use an insulating case of a height sized as a function of that of the semi-conductor; in the case there is provided a spring calibrated so as to produce the prescribed clamping force. The electric power connection is provided either by means of a threaded rod extending from the case at the upper part thereof, or by a rigid connection strip extending from the case on one of the sides thereof.
Such a device has the disadvantage of requiring a restrictive association of the semi-conductor component, its case and the clamping spring, in particular as a function of the height and diameter of the component; in addition, the connecting mode used involves a cascade of electric contacts causing successive overheatings harmful for the semi-conductor and/or mechanical stresses due to rigid connections and adversely effecting the reliability of the semi-conductor;
In another known mounting device, of the bilateral cooling type, that is to say through both faces of the semi-conductor component, clamping clips are used for clamping together two heat sinks enclosing the semi-conductor. The clip comprises a calibrated spring for obtaining the prescribed clamping force. In this case, the electric connections are formed on the heat sinks which also provide the function of electric conductors.
Such a device, transposed to unilateral cooling mounts comprising one or more semi-conductor components, has the disadvantage of having to be adapted when it is desired to use semi-conductors of different heights or with wide height tolerances, either during the original mounting, or during replacement of a semi-conductor in the place of use. The desired adaptation is obtained by means of a braided connection or by means of a rigid connection with insertion of shims or other systems for bringing to the desired dimensions. These solutions as a whole have the disadvantage of being relatively expensive.
The purpose of the present invention is more especially to overcome the above mentioned defects and to create a simple device adapted to semi-conductor power components of varying heights and facilitating the mounting and connection of said components.
Its aim is to avoid the transmission to such semi-conductor components of the forces likely to be exerted on the connection elements of the device.